Bernard Tomic, Nick Kyrgios and Thanasi Kokkinakis have been making headlines for all the wrong reasons, leaving Australian media to ask Monday: "Are the trio of stars losing the plot because they are young, stupid or victims of their own poor judgement?"

Kyrgios has been the chief culprit, picked up by on-court microphones telling Grand Slam winner Stan Wawrinka that "Kokkinakis banged your girlfriend" in an on-court sledge at the Rogers Cup in Montreal last week that infuriated the Swiss star.

The 20-year-old Kyrgios was fined USD 12,500 by the ATP Tour, which launched an investigation into the remark which could result in further action against him. He later apologised but not before his unsavoury comment sparked fierce condemnation in the women's game, led by WTA Tour chairman Stacey Allaster, tennis legend Martin Navratilova and commentator Pam Shriver.

"The statement made by Nick Kyrgios is crude and unacceptable," Allaster said, in comments echoed by Australian media. "The problem with the type of venomous poison Nick Kyrgios spewed last week is that it spreads like a cancer, entangling and embroiling others in its vitriol," wrote The Australian newspaper's Courtney Walsh.

He was referring to Kokkinakis almost coming to blows with Ryan Harrison in qualifying for the Cincinnati Masters at the weekend. Kokkinakis was agitated by a pair of call overrules by the umpire in 23-year-old Harrison's favour, pressing his complaints to annoy the American who railed about these "new age little kids".

"They are going to get hurt," Harrison said. "(Kokkinakis) is 19. If he wants to get into it, I will buryhim. Wawrinka should have decked Kyrgios and I should deck that kid."

Kokkinakis has not been in trouble before and moved Monday to distance himself from the Kyrgios controversy, slamming his friend for drawing him into it. "I let him know. I made it pretty clear that he can't be doing that. If he's got a problem, he's got to say it in private," he told Australian Associated Press of the brash Kyrgios, whose behaviour has met with outrage before.

At Wimbledon this year, Kyrgios was accused of "tanking", and he also argued with umpires and gave sarcastic answers at press conferences. While some see his behaviour as petulant and disrespectful, others view his colourful antics as good for a sport in need of characters, although he is not the only Australian to raise hackles.

Tomic, 22, has endured a turbulent career, and was most recently in the headlines over his arrest in Miami last month for failing to follow police orders over a raucous penthouse party. It came on the eve of Australia's ultimately successful Davis Cup quarter-final tie against Kazakhstan, from which Tomic was dumped after an earlier tirade against Australian tennis administrators.

While Australia boasts a rich history of quality players, including Rod Laver, Ken Rosewell, Pat Rafter and Margaret Court, Lleyton Hewitt was also a loose cannon in his youth, once labelling match officials at the French Open "spastic". He eventually matured and is now the elder statesman many feel could get the current young guns back on track, particularly in his new role as Kyrgios's coach and mentor.

As Shriver said in comments reported by Australian media after the Kyrgios and Kokkinakis fiascos: "Channel your inner Laver, Rosewell (Tony) Roche, Rafter. Bring the class again."